Ethanol Fuel Research Papers - Academia.edu (original) (raw)

- by
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- Analytical Chemistry, Ethanol Fuel, Flow Injection Analysis, Alcohol

Considering the pollution problems and energy crisis today, investigations have been focused on lowering the concentration of toxic components in combustion products and decreasing fuel consumption by using renewable alternative fuels. The effects of ethanol addition to unleaded gasoline on the performance and pollutant emission of the spark ignition engine are established both analytically and experimentally. In the present work a quasi-dimensional model was developed to study the effect of ethanol blending on the thermodynamic cycle of the engine. The Ricardo E6/US engine has been used for verification and comparison of the results of the model with experimental tests. The results of the standard ASTM methods showed that, with increasing ethanol content, the research octane number of the blended fuels increases, while the Reid vapour pressure of the blended fuels initially increases to a maximum at 10 vol % ethanol addition and then decreases. The results of the study showed that the addition of ethanol (from 0 to 30 vol %) increases the engine power, thermal efficiency, and specific fuel consumption and reduces the nitrogen oxides, carbon monoxide, and hydrocarbon emissions. The ethanol added improves the combustion process, reduces the crevices flow energy, reduces the cylinder temperature, reduces the ignition delay, speeds up the flame front propagation, and reduces the combustion duration. The high useful compression ratio, which produced maximum engine power, was directly proportional to the ethanol percentage in the mixture.

Lignocellulosic ethanol has been considered as an alternative transportation fuel. Utilization of hemicellulosic fraction in lignocelluloses is crucial in economical production of lignocellulosic ethanol. However, this fraction has not efficiently been utilized by traditional yeast Saccharomyces cerevisiae. Genetically modified S. cerevisiae, which can utilize xylose, has several limitations including low ethanol yield, redox imbalance, and undesired metabolite formation similar to native xylose utilizing yeasts. Besides, xylose uptake is a major issue, where sugar transport system plays an important role. These genetically modified and wild-type yeast strains have further been engineered for improved xylose uptake. Various techniques have been employed to facilitate the xylose transportation in these strains. The present review is focused on the sugar transport machineries, mechanisms of xylose transport, limitations and how to deal with xylose transport for xylose assimilation in ...

- by Nilesh Kumar Sharma
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- Engineering, Chemistry, Technology, Metabolic Engineering

The use of macroalgae (seaweed) as a potential source of biofuels has attracted considerable worldwide interest. Since brown algae, especially the giant kelp, grow very rapidly and contain considerable amounts of polysaccharides, coupled with low lignin content, they represent attractive candidates for bioconversion to ethanol through yeast fermentation processes. In the current study, powdered dried seaweeds (Ascophylum nodosum and Laminaria digitata) were pre-treated with dilute sulphuric acid and hydrolysed with commercially available enzymes to liberate fermentable sugars. Higher sugar concentrations were obtained from L. digitata compared with A. nodosum with glucose and rhamnose being the predominant sugars, respectively, liberated from these seaweeds. Fermentation of the resultant seaweed sugars was performed using two non-conventional yeast strains: Scheffersomyces (Pichia) stipitis and Kluyveromyces marxianus based on their abilities to utilise a wide range of sugars. Altho...

- by Graeme Walker
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- Chemistry, Food Science, Biotechnology, Bioenergy

Studies have shown that cooking fuels currently in use in the majority of Equatorial East African communities (specifically Mozambique) have a lot of adverse effects on the livelihood and health of the citizens and the environment. Kerosene and firewood cause of lot of respiratory problems in the users and also their prices are completely unstable. Project CASSAVA proposes cassava-sourced, ethanol-based cooking fuel as an alternative for these communities. Inspired by the existing models of operation in Nigeria and Zambia we plan to have a holistic and sustainable business model which is extremely favorable to both the investors and the users. Project CASSAVA plans to provide an end-to-end solution to the issue at hand by setting up versatile systems that will handle specific tasks including the processing of cassava and the cooking stove itself. The technical maintenance for this endeavor will be done in partnership with Universidade Lúrio, mainly to save on the costs of transportation and solving the problem of the language barrier. Project CASSAVA will be beneficial in terms of boosting rural agriculture, creating jobs, alleviating poverty, conserving forest from fuel wood exploitation, and preventing indoor pollution. The proposed technical and business design is available in detail, in the paper, with the aim of highlighting the benefits of this project for the development of the “other 90%” of the global population.

- by Athith Krishna and +2
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- Mozambique, Ethanol Fuel, Cassava, Biofuel and Bio Ethanol Production from Biomass

global demand for electrical power is on the rise, while tolerance for pollution and potentially hazardous forms of power generation is on the decline. Traditional forms of power generation -primarily made up of centralized fossil fuel plantsare becoming less favored due to the lack of clean, distributed power generation technologies. The need is well recognized for clean, safe and reliable forms of energy that can provide prescribed levels of power consistently, and on demand. Most forms of noncombustion electric power generation have limitations that impact wide spread use of technology, especially as a power source of electrical power (i.e. baseload power). Fuel cell technology on other hand has advanced to the point where it is viable challenger to combustionbased plants for growing numbers of baseload power application. If the cost is reduced by changing its material, this will be added an advantage to the large production of direct ethanol fuel cell production.

- by Dr. Bhadresh R Sudani
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- Electrical Engineering, Chemical Engineering, Renewable Energy, Fuel Cells

Fuel ethanol is considered one of the most important renewable fuels due to the economic and environmental benefits of its use. Lignocellulosic biomass is the most promising feedstock for producing bioethanol due to its global availability and to the energy gain that can be obtained when non-fermentable materials from biomass are used for cogeneration of heat and power. In this work, several process configurations for fuel ethanol production from lignocellulosic biomass were studied through process simulation using Aspen Plus. Some flowsheets considering the possibilities of reaction-reaction integration were taken into account among the studied process routes. The flowsheet variants were analyzed from the energy point of view utilizing as comparison criterion the energy consumption needed to produce 1 L of anhydrous ethanol. Simultaneous saccharification and cofermentation process with water recycling showed the best results accounting an energy consumption of 41.96 MJ/L EtOH. If pervaporation is used as dehydration method instead of azeotropic distillation, further energy savings can be obtained. In addition, energy balance was estimated using the results from the simulation and literature data. A net energy value of 17.65-18.93 MJ/L EtOH was calculated indicating the energy efficiency of the lignocellulosic ethanol. r

- by Nadie Ninguno
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- Environmental Engineering, Chemical Engineering, Process Integration, Ethanol Fuel

According to a recent report nearly 42 per cent Indian kids are
malnourished and stunted. The aim of our project was to develop
nutraceutical products using alfalfa as one of the components to
overcome undernourishment particularly among women and
children. The seeds of alfalfa (Medicago sativa) contain more
nutritional property when compared with other leguminous seeds. It
contains 18.9% of protein when compared with egg (13.1%), milk
(3.3%) and beef (16.5%). This paper reports the investigation results
of phytochemical analysis of alfalfa seed extracts using the procedure
of Sadasivam and Manickam (2009). The presence of proteins,
carbohydrates, saponins, phenolic compounds, alkaloids, flavonoids
etc. was observed in sprouted alfalfa seeds extracted by solvents such
as ethanol, petroleum and chloroform. The presences of proteins,
carbohydrates, saponins, alkaloids etc were confirmed by the present
investigation. Thus the cost effective nutraceutical product containing
alfalfa along with other cereals and pulses would serve the humanity
to fight undernourishment in an easy and economical way.

AbstractÐSince the creation of the National Alcohol Programme (NAP) in 1975, commonly known as`P roAlcool'', it has gone through a number of¯uctuations re¯ecting Brazilian political, economic and energy priorities. In 1996±1997 over 175 Mt of sugarcane (65% of 270 Mt harvested) was converted to ethanol fuel. The ProAlcool started as a highly innovative programme, but in recent years has lost part of its technological zeal and in certain areas is becoming stagnant. This is due to a combination of reasons, e.g. unclear energy policy, high sugar prices in the international market and lower investment in ethanol production as a result of low international oil prices. A new impetus is needed to re¯ect changing economic and energy policy in Brazil. This paper reviews the implications for ProAlcool of the new economic policies and the possibilities for restructuring the programme to guarantee its survival as a pioneering and sustainable renewable energy source. This will bring new challenges, costs and opportunities to Brazilian society. #

- by luis alberto cortez
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- Engineering, Technology, Energy Policy, International Marketing

Hydrogen blending with ethyl alcohol has been suggested as a potential non-petroleum derived substitute for current reciprocating engine fuels. The usage of hydrogen as a supplementary fuel to the ethyl alcohol± air mixture for spark ignition engines results in a considerable improvement of the engine performance and reduction of the toxic components in the exhaust gases in comparison with the conventional spark ignition gasoline engine. The indices of the engine have been studied at various ratios of hydrogen and ethyl alcohol in the mixture. The results show that the supplemental hydrogen in the ethyl alcohol±air mixture improves the combustion process and hence, improves the combustion eciency, increases the eective eciency and power of the engine, reduces the speci®c fuel consumption and reduces toxic emissions. The results were compared to those with gasoline fuel at the same engine conditions. Ó

Countries inspired by a desire to reduce greenhouse gas emissions in order to meet their Kyoto Protocol targets, have turned to ethanol fuels as a cheap and proven alternative to reduce vehicular emissions. Political instability in the Middle East has further motivated countries to develop their own fuel supply to ensure the security of supply and promote internal economic growth. The use of fuel ethanol has attracted considerable negative press and public comments in the early part of 2000s. Because of the importance of ethanol fuel as alternative to petrol, this review presents discussions outlining the various benefits and costs of using fuel ethanol with the objective of highlighting the future prospects of its use to reduce greenhouse gas emissions, provide cheap energy source for vehicles and also provide income to farmers producing bio-ethanol.

- by garba ahmed
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- Business, Ethanol Fuel, Key words, Future Prospects

For blending use in gasoline, it has been decided to develop a greenfield project for production of ethanol in Suriname. In this framework, an industrial solutions study was conducted for the definition of the plant location and configuration and the selection of the most appropriate technologies and logistics. Different alternatives for feedstock were studied, from which sugarcane was selected as the most suitable. Based on the expected gasoline demand in Suriname and the cane development program, a decision was made regarding the capacity of the ethanol distillery. Technologies in each process stage have been initially proposed based on process efficiency and site energy integration, also considering the production of raw sugar for domestic demand. Part of the molasses will be sent to a local rum factory. Cogeneration was an important aspect of the study because of the use of bagasse and trash for power generation for process and plantation demand as well as for exporting to the national grid. Vinasse from ethanol production will be concentrated and sent to the plantation as fertiliser. Domestic transportation of final products will be done by road; river and sea transport will be considered in the future. This paper shows the alternatives studied and the result for the best selection. The analysis is firstly based on the mass and energy balances, then an economic evaluation is conducted. Lessons learned from the project management's point of view were also important.

- by Raúl Sabadi
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- Project Management, Biomass, Ethanol Fuel, Power Generation

Este artigo apresenta uma reflexão sobre o desenvolvimento do álcool carburante (etanol) no Brasil. De um modo geral, no momento em que o governo brasileiro decidiu que a adição de álcool anidro à gasolina seria a alternativa nacional para reduzir a importação de petróleo e iniciou os estudos sobre a porcentagem máxima de adição de álcool anidro à gasolina, foram iniciadas relações capazes de criar um novo cenário nacional e uma tecnologia. Um coletivo ao mesmo tempo social e técnico. O argumento central é de que se por um lado era preciso existir laboratórios bem equipados, por outro era fundamental que fosse estabelecida uma política e uma cultura nacional de uso do álcool combustível. Compreender como foi possível o desenvolvimento do artefato sócio-técnico álcool hidratado (etanol) como combustível, durante o Plano Nacional do Álcool (PNA) significa, especificamente, investigar as associações sociotécnicas postas em operação para a sua constituição. Neste sentido, o artigo se apóia na Teoria Ator-Rede e busca compreender as inúmeras associações realizadas para que o álcool hidratado (etanol) viesse a se tornar um combustível automotivo no Brasil do início da década de 1980. Desta forma, o artigo segue a seguinte estrutura: (i) Apresenta a história do desenvolvimento do álcool carburante, focando nos eventos que: (a)contribuíram para a desestabilização da gasolina enquanto combustível viável no Brasil do início da década de 1970, (b)deram as condições para o uso do álcool Anidro enquanto combustível adicionado à gasolina, (c)promoveram e estabilizaram o álcool hidratado (etanol) como o combustível nacional do início dos anos de 1980; (ii) por último, o artigo realiza uma reflexão sobre a descrição do desenvolvimento do álcool combustível considerando simetricamente os fatores sociais e tecnológicos. Nesta reflexão evidencia que o conteúdo técnico e o contexto social após a consolidação do álcool combustível não são os mesmos dos de antes do surgimento desta tecnologia. Foi possível perceber que para os atores envolvidos não havia distinção entre os componentes técnicos e sociais, que os próprios atores fizeram os objetos locais serem encontrados nas esferas globais. O mundo – o Brasil, em 1979 - foi sendo composto por um novo combustível, um novo motor e um novo tipo de consumidor, ávido, curioso, disposto a completar o tanque do seu carro com o álcool hidratado.

- by Rafael Bennertz and +1
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- Renewable Energy, Actor Network Theory, Computer Networks, Energy Policy

In this work, a solid phase spectrophotometric method in association with flow injection analysis for formaldehyde determination has been developed with direct measurement of light-absorption in C 18 material. The 3,5-diacetyl-1,4-dihydrolutidine produced from the reaction between formaldehyde and fluoral P was quantitatively retained on C 18 support and the spectrophotometric detection was performed simultaneously at 412 nm. The retained complex was quickly eluted from C 18 material with the eluent stream consisting of a 50% (v/v) ethanol solution. The results showed that the proposed method is simple, rapid and the analytical response is linear in the concentration range of 0.050-1.5 mg L −1 .

- by Elsimar Leão
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- Analytical Chemistry, Ethanol Fuel, Flow Injection Analysis, Alcohol

Simultaneous determination of six trace metals in bioethanol fuel samples. Multivariate determination of six analytes with a voltammetric method. MLR aided by variable selection provided excellent quantitative predictions. Peak alignment... more

- by Sherlan Lemos
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- Mechanical Engineering, Chemical Engineering, Signal Processing, Chemometrics

This study aims at reviewing the alternative techniques for bioethanol recovery, highlighting its advantages and disadvantages, and to investigate the technical challenges facing these alternatives to be widely used. The findings showed that the integration of these techniques with the fermentation process did not meet a large acceptance in the industrial sector. The majority of conducted studies were mainly focusing on ethanol recovery from aqueous standard solution rather than the investigation of these techniques performance in fermentation-separation coupled system. In this context, pervaporation has received more attention as a promising alternative to distillation. However, some challenges are facing the integration of these techniques in the industrial scale as the fouling problem in pervaporation, the toxicity of solvent in liquid extraction, energy consumption in vacuum fermentation. It was also found that there is a lack of the technical economic analysis for these techniq...

- by HAMID ZENTOU
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- Computer Science, Chemistry, Ethanol Fuel, Biofuel

Recent studies are concerned by future energy shortage that projected to occur as a result of fossil fuel depletions. Our study was interested to use the environmental wastes as a raw material for bio-ethanol production. Kitchen wastes are one of the most distributed wastes all over the world. Starchy ingredients in the form of rice mainly are the major component of such wastes. Crude alpha amylase enzyme has been applied to convert the starch molecules into simple units of glucose. Saccharomyces cerevisiae has been subsequently used to ferment the produced glucose units into bioethanol anaerobically. The obtained results showed that 40% rice substrate is the optimum concentration to produce the highest glucose units at 417.9 mg/dl. However, the higher concentration of the substrate (rice) was recorded as a blocking agent for glucose production. On the other hand, the higher percentage of alpha amylase (100 µl) was recorded as the most preferable one to produce the most elevated glucose concentration of approximately 482.5 mg /dl. The highest bioethanol production of 423.5 mg/dlwas obtained after anaerobic fermentation of the free yeast cells at 30 o C without shaking. The produced bio-ethanol compared with standard 25% ethanol was separated by using amicon cell ultra-filtration at different nitrogen pressures. Chitosan and sodium alginate membranes were prepared to be used in the bioethanol/water separation process. Chitosan and sodium alginate membranes were characterized by SEM and IEC. The hydrophilicity/hydrophobicity of the prepared membranes were investigated using contact angle.

- by Ranya Amer
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- Chemistry, Ethanol Fuel, Ethanol

A capillary zone electrophoresis method using indirect UV detection for the analysis of chloride and sulfate in alcohol fuel samples was developed. The anions were analyzed in less than 3 min using an electrolyte containing 10 mmol l À1 chromate and 0.75 mmol l À1 hexamethonium bromide (HMB) as electroosmotic flow modifier. Coefficients of variation were better than 0.6% for migration time (n=10) and between 2.05 and 2.82% for peak area repeatabilities. Analytical curves of peak area versus concentration in the range of 0.065-0.65 mg kg À1 for chloride and 0.25-4.0 mg kg À1 for sulfate were linear with coefficients of correlation higher than 0.9996. The limits of detection for sulfate and chloride were 0.033 and 0.041 mg kg À1 , respectively. Recovery values ranged from 85 to 103%. The method was successfully applied for the quantification of sulfate and chloride in five alcohol fuel samples. The concentration of sulfate varied from 0.45 to 3.12 mg kg À1 . Chloride concentrations were below the method's LOD.

- by Luiz Pontes
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- Engineering, Analytical Chemistry, Filtration, Capillary electrophoresis

The increased concern for the security of the oil supply and the negative impact of fossil fuels on the environment, particularly greenhouse gas emissions, has put pressure on society to find renewable fuel alternatives. The most common renewable fuel today is ethanol produced from sugar or grain (starch); however, this raw material base will not be sufficient. Consequently, future large-scale use of ethanol will most certainly have to be based on production from lignocellulosic materials. This review gives an overview of the new technologies required and the advances achieved in recent years to bring lignocellulosic ethanol towards industrial production. One of the major challenges is to optimize the integration of process engineering, fermentation technology, enzyme engineering and metabolic engineering.

- by Guido Zacchi
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- Engineering, Chemical Engineering, Environmental Science, Chemistry
- by Maria Teresa Ribeiro Borges
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- Chemistry, Ethanol Fuel

Aiming to broaden the base of knowledge about wild yeasts, four new indigenous strains were isolated from corn residues, and phylogenetic-tree assemblings on ITS and LSU regions indicated they belong to Meyerozyma caribbica . Yeasts were cultivated under full- and micro-aerobiosis, starting with low or high cell-density inoculum, in synthetic medium or corn hydrolysate containing glucose and/or xylose. Cells were able to assimilate both monosaccharides, albeit by different metabolic routes (fermentative or respiratory). They grew faster in glucose, with lag phases ~ 10 h shorter than in xylose. The hexose exhaustion occurred between 24 and 34 h, while xylose was entirely consumed in the last few hours of cultivation (44–48 h). In batch fermentation in synthetic medium with high cell density, under full-aerobiosis, 18–20 g glucose l −1 were exhausted in 4–6 h, with a production of 6.5–7.0 g ethanol l −1 . In the xylose medium, cells needed > 12 h to consume the carbohydrate, and instead of ethanol, cells released 4.4–6.4 g l −1 xylitol. Under micro-aerobiosis, yeasts were unable to assimilate xylose, and glucose was more slowly consumed, although the ethanol yield was the theoretical maximum. When inoculated into the hydrolysate, cells needed 4–6 h to deplete glucose, and xylose had a maximum consumption of 57%. Considering that the hydrolysate contained ~ 3 g l −1 acetic acid, it probably has impaired sugar metabolism. Thus, this study increases the fund of knowledge regarding indigenous yeasts and reveals the biotechnological potential of these strains. Graphical abstract

- by Viviani Tadioto
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- Biochemistry, Technology, Food Science, Medicine

Effect of particle size distribution on sensor characteristics of nano-Bi fixed electrode has been investigated using square wave anodic stripping voltammetry. Bi nanopowders with various particle size distributions were synthesized by gas condensation (GC) method with the change of chamber pressure. As the chamber pressure decreased, the size of Bi nanopowder became smaller with narrower distribution due to a shorter residence time of Bi vapor. The square wave anodic stripping voltammograms (SWASV) showed well-defined and highly reproducible peaks at À 1.2 V, À 0.8 V and À 0.6 V (vs. SCE), which are closely related to the oxidation of Zn, Cd and Pb, respectively. The sensitivity and detection limit of the nano-Bi fixed electrode were quantitatively estimated from the analyses of SWASV. From the results, it is concluded that as the size of Bi nanopowder becomes smaller with narrower particle size distribution, the sensitivity and detection limit of sensor electrode for Zn, Cd and Pb are improved, which is ascribed to the increase in electrochemical-active surface area.

- by Priscila Cervini
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- Analytical Chemistry, Electroanalysis, Ethanol Fuel, Particle Size Distribution
- by Tatsuji Seki
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- Engineering, Genetics, Technology, Biology

A new pretreatment technology using dilute ammonium hydroxide was evaluated for ethanol production on sorghum. Sorghum fibers, ammonia, and water at a ratio of 1:0.14:8 were heated to 160°C and held for 1 h under 140-160 psi pressure. Approximately, 44% lignin and 35% hemicellulose were removed during the process. Hydrolysis of untreated and dilute ammonia pretreated fibers was carried out at 10% dry solids at an enzyme concentration of 60 FPU Spezyme CP and 64 CBU Novozyme 188/g glucan. Cellulose digestibility was higher (84%) for ammonia pretreated sorghum as compared to untreated sorghum (38%). Fermentations with Saccharomyces cerevisiae D 5 A resulted in 24 g ethanol /100 g dry biomass for dilute ammonia pretreated sorghum and 9 g ethanol /100 g dry biomass for untreated sorghum.

- by Giovanna Aita
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- Chemistry, Technology, Biomass, Medicine

Aiming to obtain rapid fermentations with high ethanol yields and a retention of high final viabilities (responses), a 2 3 full-factorial central composite design combined with response surface methodology was employed using inoculum size, sucrose concentration, and temperature as independent variables. From this statistical treatment, two well-fitted regression equations having coefficients significant at the 5% level were obtained to predict the viability and ethanol production responses. Three-dimensional response surfaces showed that increasing temperatures had greater negative effects on viability than on ethanol production. Increasing sucrose concentrations improved both ethanol production and viability. The interactions between the inoculum size and the sucrose concentrations had no significant effect on viability. Thus, the lowering of the process temperature is recommended in order to minimize cell mortality and maintain high levels of ethanol production when the temperature is on the increase in the industrial reactor. Optimized conditions (200 g/l initial sucrose, 40 g/l of dry cell mass, 30°C) were experimentally confirmed and the optimal responses are 80.8±2.0 g/l of maximal ethanol plus a viability retention of 99.0±3.0% for a 4-h fermentation period. During consecutive fermentations with cell reuse, the yeast cell viability has to be kept at a high level in order to prevent the collapse of the process.

- by João Tognolli
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- Food Science, Biomass, Response Surface Methodology, Multidisciplinary
- by Huiyun Zhou
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- Ethanol Fuel, Fermentation, Hydrolysis

A general theoretical model to predict evaporative ethanol losses during the industrial process of batch alcohol production by fermentation ls suggested. The model takes into account the combined effects of several yield loss factors. It also includes kinetic equations to predict product formation as a basis for calculating evaporative rates. The model has been compared wlth others reported ln the literature and a compilation of experimental data from different discontinuous processes has been used for verification, at both industrial and laboratory levels. The results show the suggested model to yield higher theoretical consistency as well as better adaptability to actual experimental data.

- by Luis Perez
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- Chemical Engineering, Chemistry, Ethanol Fuel, Ethanol

Batch distillation applied to hydrous ethanol fuel (HEF) production on a small scale still requires operating conditions that ensure optimal top product quality and productivity. The aim of this study is to statistically validate a batch still through the employment of response surface methodology (RSM). Operational and productivity parameters were formulated in order to guarantee quality compliance with the legal requirements for the top product concentration, besides providing support information to control the production of HEF on a small scale. The reboiler control and dephlegmator temperatures maintained within the range of 97.5 to 99.5°C and 60 to 70°C, respectively, combined with a variable reflux ratio, was satisfactory in obtaining a top product concentration, in accordance with legal regulations, as well as high productivity. The results of this study may contribute to the assembly of a simple and low-cost batch distillation control system.

- by RONALDO HOFFMANN
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- Process Optimization, Ethanol Fuel, Factorial Design, Batch Distillation
- by Carlos Cardona–Alzate
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- Ethanol Fuel, Fermentation, Hydrolysis

A graphite-polyurethane composite modified with 2-benzothiazolethiol organofunctionalized silica was evaluated as an alternative electrode in the determination of Cu 2+ ions in ethanol fuel samples, on the basis of a differential pulse anodic stripping voltammetry procedure. This metal can be quantified by mixing ethanol fuel with 0.10 mol L À1 KNO 3 aqueous solution and subsequent voltammetric measurement after the accumulation step. A maximum limit of 70% (v/v) ethanol in potassium nitrate aqueous solution was obtained for voltammetric measurements without loss of sensitivity for metal species. Factors affecting the pre-concentration and stripping steps were investigated and optimum conditions were employed to develop the analytical procedure. Using 20 min of accumulation time, the linear range of 0.1-1.2 lmol L À1 was obtained with the limit of detection of 3.9 Â 10 À8 mol L À1 . The developed electrode was successfully applied to determine Cu 2+ in commercial ethanol fuel samples. The proposed method was compared with a traditional analytical technique, the flame atomic absorption spectrometry, and no significant differences between the results obtained by both methods were observed according to statistical evaluation.

- by Glimaldo Marino
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- Mechanical Engineering, Chemical Engineering, Mixing, Ethanol Fuel

Background: Drying is currently the most frequently used conservation method for cereal grain, which in temperate climates consumes a major part of process energy. Airtight storage of moist feed grain using the biocontrol yeast Pichia anomala as biopreservation agent can substantially reduce the process energy for grain storage. In this study we tested the potential of moist stored grain for bioethanol production. Results: The ethanol yield from moist wheat was enhanced by 14% compared with the control obtained from traditionally (dry) stored grain. This enhancement was observed independently of whether or not P. anomala was added to the storage system, indicating that P. anomala does not impair ethanol fermentation. Starch and sugar analyses showed that during pre-treatment the starch of moist grain was better degraded by amylase treatment than that of the dry grain. Additional pre-treatment with cellulose and hemicellulose-degrading enzymes did not further increase the total ethanol yield. Sugar analysis after this pre-treatment showed an increased release of sugars not fermentable by Saccharomyces cerevisiae. Conclusion: The ethanol yield from wheat grain is increased by airtight storage of moist grain, which in addition can save substantial amounts of energy used for drying the grain. This provides a new opportunity to increase the sustainability of bioethanol production.

- by Volkmar Passoth
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- Chemical Engineering, Environmental Science, Industrial Biotechnology, Medicine

Tropical countries, such as Brazil and Colombia, have the possibility of using agricultural lands for growing biomass to produce bio-fuels such as biodiesel and ethanol. This study applies an energy analysis to the production process of anhydrous ethanol obtained from the hydrolysis of starch and cellulosic and hemicellulosic material present in the banana fruit and its residual biomass. Four different production routes were analyzed: acid hydrolysis of amylaceous material (banana pulp and banana fruit) and enzymatic hydrolysis of lignocellulosic material (flower stalk and banana skin). The analysis considered banana plant cultivation, feedstock transport, hydrolysis, fermentation, distillation, dehydration, residue treatment and utility plant. The best indexes were obtained for amylaceous material for which mass performance varied from 346.

- by hector velasquez
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- Mechanical Engineering, Civil Engineering, Chemistry, Energy

- by Joseph Akunna
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- Chemistry, Food Science, Biotechnology, Bioenergy

The aim of this work was performed to develop a milder and cost effective extraction procedure for Beta-glucan (BG) from two types of S. cerevisiae, the returned Baker's yeast "RBY" and yeast remaining after ethanol fermentation "EFY" using different chemical extraction steps. The current results revealed that the carbohydrate percent in yeast biomass was considerably increased by the different extraction steps (from 37.64 to 92.41% and from 41.37 to 93.46% in case of RBY and EFY, respectively). On the other hand, the percent of protein in yeast biomass was decreased by the different extraction steps (from 41.91 to 1.28% and from 36.32 to 1.15% in the two cases, respectively). The extracted dry biomass in the two cases were analysed by Fourier Transform Infrared (FTIR) spectra. This method of β-glucan extraction steps has been shown to produce great yields of β-glucan with maintaining their purity and native structure.

- by Mohamed Orban
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- Saccharomyces cerevisiae, Ethanol Fuel, Ethanol, Yeast
- by Carlos Cardona–Alzate
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- Ethanol Fuel

In the present study, it was try to investigate the effects of green tea
on some biochemical parameters of male albino rats with ethanol
toxicity. All rats were divided into 4groups, Group 1 (controls) and
group 2 (ethanol control) remaining 2 groups were treated with
ethanol and green tea extract for 30 days. The results showed
significant elevation in the level of ACP, sugar (P<0.001), and
Bilirubin (P<0.005) where as liver weight Showed no significant
elevation with ethanol as compared to normal. These changes in all
parameters indicated liver injury and hepatomegaly due to the
enhancement in the ROS which causes decrease in antioxidants of
body defense system. The green tea extract with ethanol treatment
was able to restore these changes at various levels of significance
comparing with the control group of rats. These data suggested that
the green tea exerts improvement in liver function by preventing the
production of reactive oxygen species (ROS) and enhancing the
antioxidant defense system capacity. Thus green tea extract has
protective effects against ethanol toxicity.

The rapid expansion of ethanol production from sugarcane in Brazil has raised a number of questions regarding its negative consequences and sustainability. Positive impacts are the elimination of lead compounds from gasoline and the reduction of noxious emissions. There is also the reduction of CO 2 emissions, since sugarcane ethanol requires only a small amount of fossil fuels for its production, being thus a renewable fuel. These positive impacts are particularly noticeable in the air quality improvement of metropolitan areas but also in rural areas where mechanized harvesting of green cane is being introduced, eliminating the burning of sugarcane. Negative impacts such as future large-scale ethanol production from sugarcane might lead to the destruction or damage of high-biodiversity areas, deforestation, degradation or damaging of soils through the use of chemicals and soil decarbonization, water resources contamination or depletion, competition between food and fuel production decreasing food security and a worsening of labor conditions on the fields. These questions are discussed here, with the purpose of clarifying the sustainability aspects of ethanol production from sugarcane mainly in São Paulo State, where more than 60% of Brazil's sugarcane plantations are located and are responsible for 62% of ethanol production.

- by Jose Goldemberg
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- Environmental Science, Air Quality, Energy Policy, Multidisciplinary

This research assessed the economic effect of corn-based fuel ethanol production on agriculture and the state economy in Alabama. The results showed that in the short run a 15 million gallon per year plant will be profitable. This will... more

- by Robert Zabawa
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- Economics, Energy Economics, Agricultural Economics, Meeting

Sorghum is a major cereal crop in the USA. However, sorghum has been underutilized as a renewable feedstock for bioenergy. The goal of this research was to improve the bioconversion eYciency for biofuels and biobased products from processed sorghum. The main focus was to understand the relationship among "genetics-structure-function-conversion" and the key factors impacting ethanol production, as well as to develop an energy life cycle analysis model (ELCAM) to quantify and prioritize the saving potential from factors identiWed in this research. Genetic lines with extremely high and low ethanol fermentation eYciency and some speciWc attributes that may be manipulated to improve the bioconversion rate of sorghum were identiWed. In general, ethanol yield increased as starch content increased. However, no linear relationship between starch content and fermentation eYciency was found. Key factors aVecting the ethanol fermentation eYciency of sorghum include protein digestibility, level of extractable proteins, protein and starch interaction, mash viscosity, amount of phenolic compounds, ratio of amylose to amylopectin, and formation of amylose-lipid complexes in the mash. A platform ELCAM with a base case showed a positive net energy value (NEV) = 25,500 Btu/gal EtOH. ELCAM cases were used to identify factors that most impact sorghum use. For example, a yield increase of 40 bu/ac resulted in NEV increasing from 7 million to 12 million Btu/ac. An 8% increase in starch provided an incremental 1.2 million Btu/ac.

- by Xiaorong Wu
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- Genetics, Industrial Biotechnology, Starch, Ethanol Fuel

Background: To make lignocellulosic fuel ethanol economically competitive with fossil fuels, it is necessary to reduce the production cost. One way to achieve this is by increasing the substrate concentration in the production process, and thus reduce the energy demand in the final distillation of the fermentation broth. However, increased substrate concentration in simultaneous saccharification and fermentation (SSF) processes has been shown to result in reduced ethanol yields and severe stirring problems. Because the SSF medium is being continuously hydrolyzed, running the process in fed-batch mode could potentially reduce the stirring problems and lead to increased ethanol yields in highsolids SSF. Different enzyme feeding strategies, with the enzymes either present in the reactor from start-up or fed into the reactor together with the substrate, have been studied, along with the influence of the enzyme feeding strategy on the final ethanol yield and productivity. Results: In the present study, SSF was run successfully with 10% and 14% water-insoluble solids (WIS) in batch and fedbatch mode. The mixing of the material in the reactor was significantly better in fed-batch than batch mode, and similarly high or higher ethanol yields were achieved in fed-batch mode compared with batch SSF in some cases. No general trend in the dependence of ethanol yield on enzyme feeding strategy was found. Conclusions: The optimum enzyme feeding strategy appears to depend on the conditions during SSF, such as the WIS concentration and the concentration of inhibitory compounds in the SSF medium.

- by Guido Zacchi
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- Chemical Engineering, Chemistry, Industrial Biotechnology, Medicine
- by Chris de Visser
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- Sustainable Development, Ethanol Fuel, Environmental Sciences, Sugar Beet

- by Heloisa Pinheiro
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- Analytical Chemistry, Ethanol Fuel, Flow Injection Analysis, Alcohol

The costs of oil dependence, the environmental external costs of fossil fuels, or the promotion of agricultural development, has justified a number of measures of state intervention to expand the domestic market of biofuels, assuming that state intervention is necessary and sufficient condition for achieving this aim. After analyzing the political and economic elements in the Brazilian ethanol sector in historical perspective, in this article we argue that the expansion or contraction of the market should not be understood as an effect of a particular policies determined by the regulatory state. Regarding this, we argue the trends on the market development reflect the effects of aprevious underlying relationship, which is determined by the convergence or divergence over time of the opportunity costs of government and agribusiness. Our analysis shows that the effectiveness of a policy of energy diversification as the promotion of biofuels depends on the economic benefits and political rents generated by expanding the use of ethanol. These restrictions can be extrapolated as part of the cost-effectiveness analysis of public policies related to the sector in other countries.

- by Revista Derecho PUCP and +1
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- Renewable Energy, Road Transport, Energy Policy, Brazil

- by luis alberto cortez
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- Engineering, Technology, Energy Policy, International Marketing

Eight strains of Kluyveromyces marxianus were screened, and all of them were found to ferment the aldopentose d -xylose directly to ethanol under aerobic conditions. One of these strains, K. marxianus SUB-80-S, was grown in a medium containing 20 g of d -xylose per liter, and the following results were obtained: maximum ethanol concentration, 5.6 g/liter; ethanol yield, 0.28 g of ethanol per g of d -xylose (55% of theoretical); maximum specific growth rate, 0.12 h −1 ; 100% d -xylose utilization was completed in 48 h.

- by pratima bajpai
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- Chemistry, Medicine, Multidisciplinary, Ethanol Fuel

Epidemiological studies have found a positive association between coffee consumption and a lower risk of cardiovascular disorders, some cancers, diabetes, Parkinson and Alzheimer disease. Coffee consumption, however, has also been linked to an increased risk of developing some types of cancer, including bladder cancer in adults and leukemia in children of mothers who drink coffee during pregnancy. Since cancer is driven by the accumulation of DNA alterations, the ability of the coffee constituent caffeic acid to induce DNA damage in cells may play a role in the carcinogenic potential of this beverage. This carcinogenic potential may be exacerbated in cells with DNA repair defects. People with the genetic disease Fanconi Anemia have DNA repair deficiencies and are predisposed to several cancers, particularly acute myeloid leukemia. Defects in the DNA repair protein Fanconi Anemia D2 (FANCD2) also play an important role in the development of a variety of cancers (e.g., bladder cancer) in people without this genetic disease. This communication shows that cells deficient in FANCD2 are hypersensitive to the cytotoxicity (clonogenic assay) and DNA damage (γ-H2AX and 53BP1 focus assay) induced by caffeic acid and by a commercial lyophilized coffee extract. These data suggest that people with Fanconi Anemia, or healthy people who develop sporadic mutations in FANCD2, may be hypersensitive to the carcinogenic activity of coffee.

- by Fátima Aparecida Almeida Costa
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- Chemistry, Food Science, Ethanol Fuel, Fermentation
- by Guido Zacchi
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- Chemical Engineering, Production, Recycling, Biology

An encapsulated reconstituted cell-free enzyme system was developed through liquid-droplet forming method by using endogenous glycolytic and fermentation enzymes from yeast cells and exogenously added saccharification enzymes, cofactors, and ATPase. It was evaluated for bio-ethanol production through simultaneous saccharification and fermentation (SSF) at various temperatures, pH, and cellfree enzyme and substrate concentrations. Using 1% starch as substrate, encapsulated system illustrated maximum efficiency at 45 • C and pH 7.0. SSF with encapsulated and bare reconstituted cell-free enzyme systems produced 3.47 g/L and 2.98 g/L bio-ethanol corresponding to 62% and 53% of maximum theoretical yield, respectively. It was explicable that encapsulated system provided better substrate utilization and product formation at elevated temperatures than bare system. Kinetic profile of SSF process of both systems was affected differently by variations in pH, temperature, and substrate and cell-free enzyme concentrations. Under appropriate conditions, system retained 90%, 64%, and 40% of initial enzyme concentration and produced 3.21, 2.24, and 0.83 g/L bio-ethanol after 5, 10, and 15 consecutive batches, respectively. The current system offered several advantages and was superior compared to previously reported SSF systems. This system can effectively overcome the major barriers associated with successful development of SSF processes for bio-ethanol production on an industrial scale.

The mezcal production in the state of Michoacan, located in central Mexico, is considered an informal activity with little to no regulation. The raw material is obtained from wild Agave populations, where dozens of species proliferate without any type of management. Consequently, the process is inefficient and the product obtained does not comply with the Mexican Mezcal Regulatory Council’s standards. Therefore, the object of this study was to analyze fermentation using a variety of yeast strains at the bioreactor level in order to establish statistical differences in the production of ethanol and biomass. Five yeasts ( Kluyveromyces marxianus, Zygosaccharomyces bailli, Zygosaccharomyces rouxi, Pichia kluyveri and Isstchenkia terricola ) were added to YPD medium with Agave cupreata juice. Each yeast was inoculated for 18-24 hours, stirring at 180 rpm at a temperature of 28 ° C. In order to carry out the fermentation process, it was placed in a bioreactor for 60 hours at a temperatur...

- by Alberto Madrigal
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- Chemistry, Food Science, Ethanol Fuel, Yeast

- by Shuvashish Behera
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- Engineering, Chemistry, Technology, Metabolic Engineering